Improvement of Fault Ride-Through Capability of Wind Turbine Driven DFIG Using Dynamic Voltage Restorer

Abstract: This paper concentrates on the fault ride-through capability of a Doubly Fed Induction Generator (DFIG) - based wind turbine using a Dynamic Voltage Restorer (DVR). The voltage variations from normal operating range due to faults may lead to improper disconnection of wind turbines, so the DVR is included to protect wind turbines from voltage disturbances. DVR can compensate the faulty line voltage, while the DFIG wind turbine can continue its nominal operation as demanded in actual grid codes. In this paper, the Simulation results for a 2MW wind energy conversion turbine are presented for without DVR and with DVR for L-G fault (asymmetrical grid fault) and L-L-L fault (symmetrical grid fault). The results clearly show that there is improvement in stator voltage, stator and rotor currents, and active and reactive powers when wind turbine is driven with DVR.

Keywords: Doubly Fed Induction Generator, WECS, DVR, Asymmetrical and Symmetrical faults.